Despite limited toxicological studies of UV filters in corals, legislative activity in Hawaii and other locations has led to bans on the sale and/or use of sunscreens containing the active ingredient oxybenzone (BP-3). The few published coral toxicity studies on BP-3 are difficult to compare due to varied methodology and inconstant acute and chronic toxicological responses. Therefore, I conducted repeated acute (96-hour) toxicity tests with copper and a common hard coral, Galaxea fascicularis, based on standard invertebrate toxicity testing guidelines to determine the species’ utility as a standard testing organism as well as the utility of copper as a positive control. This was followed by acute and chronic (28-day) toxicity tests with BP-3 using the same methodology to determine this compound’s toxicity. Multiple endpoints pertinent to risk assessments (mortality and growth) and additional biological endpoints were examined. Using these results, preliminary risk quotients of BP-3 and Galaxea fascicularis were calculated.